Google has been collecting information about schoolchildren's browsing habits despite signing a pledge saying it was committed to their privacy, the Electronic Frontier Foundation said in a complaint filed Tuesday.

The digital rights group said Google's use of the data, collected through its Google for Education program, puts the company in breach of Section 5 of the Federal Communications Act and asked the Federal Trade Commission to investigate.

“Despite publicly promising not to, Google mines students’ browsing data and other information, and uses it for the company’s own purposes," the EFF said.

Google and Microsoft both have extensive programs for educators. Google sells low-cost Chromebooks and tablets, and it offers free apps that teachers and students can use in the classroom.

The tools can be a boon to cash-strapped schools, which have signed up in big numbers. Last month, Google said more than 50 million students and teachers around the globe were using Google Apps for Education, along with 10 million Chromebooks. The Google-powered laptops are "the best-selling device in U.S. K-12 schools," according to Google.

But the EFF has some issues with the way Google delivers those services. It says the company records everything students do while they're logged into their Google accounts, regardless of the device or browser they're using, including their search history, the search results they click on and the videos they watch on YouTube.

Google aggregates and anonymizes the data collected through its education services, the EFF said, but not when the students are using other Google services. And it argues that truly anonymizing data is "difficult to the point of being impossible," especially when it's tied to identifiable accounts at the time of collection.

Google's practices "fly in the face of commitments made when it signed the Student Privacy Pledge," the EFF said, referring to a document signed by 200 companies including Google, Microsoft and Apple.

In light of the pledge, the EFF says, Google's collection of student data amounts to an unfair or deceptive business practice. It wants the FTC to investigate, force Google to destroy the student data it's collected, and bar it from collecting any more.

Google declined to discuss the specifics of the EFF's allegations but provided a statement: “Our services enable students everywhere to learn and keep their information private and secure. While we appreciate EFF's focus on student privacy, we are confident that these tools comply with both the law and our promises, including the Student Privacy Pledge."

The EFF apparently won at least one concession from Google. It had an issue with the way the Chrome Sync feature in the Chrome browser is turned on by default in Chromebooks and shares student data across different Google services. Google told the EFF it would soon disable that setting in Chromebooks sold to schools.

"While that is a small step in the right direction, it doesn’t go nearly far enough to correct the violations of the Student Privacy Pledge currently inherent in Chromebooks being distributed to schools," the EFF said.